Traffic control apparatus



April 1938. w. c. NEIN ET AL 2,114,968

TRAFFIC CONTROL APPARATUS Filed March 15, 1955 4 Sheets-Sheet l[NVENTOR5 Mil/4M C A-v/v A/vp 7/?04445/4/ M1215) ATTORNEKfi April 19,1938.

w. c. NElN ET AL 2,114,968

- TRAFFIC CONTROL APPARATUS Filed March 15, 1935 4 Sheets-Sheet 3 75 57/5 Phase A (/n/ INVENTORS W/u/AM C. IVE/N 4w 72mm: 14/ V/IPEY A TTORNEx9 April 19, 1938. w. c. NEIN ET AL 2,114,968

TRAFFI C CONTROL APPARATUS Filed March 13, 1955 4 Sheets-Sheet 4INVENTORJ MAL/4M C/Vzm AND 71 mm: W 144m B y maf M A TTORNEYJ PatentedApr. 19, 1938 UNITED STATES PATENT OFFICE TRAFFIC CONTROL APPARATUSApplication March 13, 1935, Serial No. 10,776

22 Claims.

This invention relates to traffic control systems and has for a generalobject the provision of a system and apparatus therefor for the controlof traflic at an intersection of a plurality of mutually interferingtraflic lanes.

An object of the invention is to provide an improved automatic system oftraffic actuated traflic control, capable of numerous differentassociations and of especial utility at the intersection of more thantwo traflic lanes.

Another object is to provide a control apparatus comprised of a numberof standard, individual and similar mechanical units or sections suchthat for the intersection of any number of interfering trafiic coursesor routes the control apparatus may be assembled of a corresponding number of these units.

A further object of the invention is to provide an apparatus of thischaracter having separate right of way indicators for each of theseveral interfering vehicular trafilc lanes, and in addition thereto, afurther separate set of signal indicators and period of right of way forpedestrians.

Another object is to provide by one arrangement a traiiic control systemin which right of way remains displayed on the lane to which it was lastaccorded until transferred to some other lane where actuation of atraffic actuatabledevice has occurred, and. by another arrangement atramc control system in which right of way always reverts automaticallyto pedestrians only, after the last vehicle actuation and in the absenceof further actuation, and which provides a pedestrian right of wayinterval automatically in each cycle of signal indications.

A further object is to provide apparatus of this character which willutilize a minimum of simple and ruggedly constructed parts which willoperate for long periods of time free from electrical and mechanicaldifficulties.

Still another object is to provide a trafiic control system of thecharacter disclosed in Which right of way is accorded to traificapproaching the intersection for a minimum or greater period of time,the length of the right of way period beyond the minimum being entirelydependent upon the traffic conditions existing on the several lanes.

Further and more specific objects will subsequently appear in thefollowing specification, reference now being had to the accompanyingdrawings, wherein:

Figure 1 illustrates diagrammatically the intersection of a plurality ofvehicular traffic lanes and their accompanying pedestrian paths, withapparatus embodying the present system associated therewith. It will beunderstood that while this figure shows three vehicle lanes for examplethis invention may readily be applied to two or more interfering lanes.

Figure 2 represents diagrammatically a form of signal for indicatingright of way to each of the intersecting vehicle lanes.

Figure 3 similarly represents a form of signal for indicating right ofway to pedestrians.

Figure 4 shows somewhat diagrammatically a unit or portion of thecontrol apparatus, vehicle actuatable device, and the interconnectionsrequired for one of the interfering traflic lanes or phases, these beingsimilar to corresponding units or portions of the control apparatusrequired for each other phase.

Figure 5 represents schematically the interconnections between theseveral units of the control apparatus.

Figure 6 shows diagrammatically an alternative type of vehicleactuatable device which may be substituted for the embodiment of thisdevice shown in Figure 4.

Figure 7 represents diagrammatically a unit or portion of the controlapparatus, generally resembling that of Figure 4, except that thestructure herein shown is adapted for one embodiment of the pedestrianor phase P unit and has no actuatable device associated with it. It isconnected to the other units of the control apparatus in the mannerindicated in the figure, and shown in Figure 5.

Figure 8 shows an illustrative view of the IM relays of the severaltiming units, of which one unit is shown in Figure 4, and their commoninterlocking tongue T.

Referring to Figure 1 the intersection of a plurality of trafiic lanesA, B, and C and their associated pedestrian paths P are shown. Signalsfor indicating right of way to each of the vehicular traiiic lanes andthe control apparatus therefor may for instance be conveniently locatedin unit Z, and signals for the pedestrian phase or element may forexample be suitably displayed from posts W in the several pedestrianpaths, or any other well known signal arrangement may be employed. Avehicle actuatable device X, which upon the arrival of a vehicle to passthru the intersection will control an operating circuit, is

located in each lane and is connected to the controlling apparatus.Right of way is accorded to one interfering lane, or phase, at a timeand there may be any desired number of phases.

Right of way indications may be displayed by any conventional system ofcolored lamps, lenses,

and reflectors which may display, for instance, green, red, or yellow,indicating respectively right of way (go), interruption of right of way(stop), or an impending change in right of way from one lane to another(caution).

The function of the control apparatus is to control changes ofindication of the signals W, Z, to the several elements or phases, andits operation is governed by actuation of the vehicle responsive devicesX so that in effect right of way is jointly controlled by the vehicleresponsive devices and the control mechanism.

Some features of the traflic control system according to this inventionmay be briefly de scribed as follows:

The control mechanism cyclically tests the vehicular phases and thepedestrian phase one at a time in a predetermined order, and if the lanebeing tested is one on which a trafiic unit is approaching theintersection and has operated the tlafilc responsive device therein,right of way is accorded to this lane and interrupted on all otherlanes. Should there be no such vehicle approaching the intersection orawaiting right of way on the lane being tested, the controller does noteffect transfer of right of way to that lane but proceeds to test thenext phase in its cycle in a similar fashion. When right of way istransferred in response to actuation, the testing operation on the nextphase is delayed for a predetermined minimum or greater period of time,but not longer than a predetermined maximum period.

Actuations of the responsive device in a lane to which right of way isthen being accorded, if. the portion of the ri ht of way remaining onthat lane is too short for the actuating vehicle to pass through theintersection, will either produce an extension of the period or affectthe control in such a manner that right of way will be returned to thesaid lane when the control mechanism next tests this phase.

In the particular embodiment illustrated there is no actuatable devicein the pedestrian phase and for this reason right of way is accorded tothis phase for a predetermined period each time this phase is tested. Aswill later appear, the pedestrian paths may, however, be equipped withactuatable devices such as push buttons accessible for actuation bypersons desirous of crossing the intersection, whereupon the pedestrianphase is only accorded right of way upon specific demand or actuation,similar to the other phases. In this case, in the absence of actuationof any of. the vehicle or pedestrian responsive devices in all the otherphases, right of way will remain indefinitely on the phase where thelast demand was received.

On the other hand, trafiic responsive devices may be omitted from one ormore of the vehicle lanes whereupon right of way is accorded to each ofsuch lanes for a predetermined period each time these phases are tested.Operation of the controller in according right of way to a lane havingno traflic responsive device is in effect the same as if the said lanecontained a responsive device which was being continuously actuated byan uninterrupted flow of traffic.

While the general operation of an automatic traffic control systemembodying this invention has been outlined above, and it has beenpointed out that the apparatus may be comprised of traffic responsivemeans and signal indicating devices, each connected to a controlmechanism of several interconnected units, the construction andoperation of one specific and complete system embodying the inventionwill now be described in detail.

In Figure 1 of the drawings the vehicle actuatable devices X may be ofthe type shown in section in Figure 4 or 6, or may be of any othersuitable design. In the type illustrated in Figure 4, a U-shaped steeltrough 2i is shown set into the roadway. Two rust proof metal plates or00- acting contactors 22, are spaced apart and supported by resilientrubber 23 in the trough in such a manner that the weight of a vehiclewill cause the contactors to flex into contact with one another andoperate an electrical circuit. For mechanical protection there is placedon the rubher a steel plate 24 to be traversed by the wheel V of apassing vehicle. Contact between the plates closes a circuit from L3,one side of a D. C. power line, to a lead 51. Other types of pressureoperated switches which are operated by the weight of vehiclestraversing them, or any other form of device which will control anoperating circuit upon the approach of a vehicle to the intersection maybe employed in lieu of. the devices illustrated.

In Figure 6 is shown a detecting or vehicle responsive device havin asolenoid winding U and a core F which is depressible by a lever L. As avehicle wheel passes over this lever L embedded in the pavement, themovement of the core causes a change in the current value in thesolenoid winding U and the change may be utilized to start a sequence ofoperations.

The control mechanism for operating the indications of the severalsignals is comprised of an individual unit for each phase, with theunits for the several phases interconnected, as will be shown. The partsand electrical circuits for one unit, for example, the phase B unit, andsimilar to the parts and circuits in the unit for any other phase, areshown diagrammatically in Figure 4. Traific through an intersectionhaving any number of interfering traffic lanes or phases may beefficiently dispatched by a system of this character, each phase havingits individual vehicle responsive devices and signals, connected to aseparate unit in the control mechanism.

A single transformer-rectifier assembly furnishes a supply of directcurrent for the direct current relays in all the units of the controlmechanism. LI and L2 are terminals of a source of alternating current ofsuitable potential. Direct current is obtained therefrom. at theterminals marked L3 and L4 by means of a transformer 26 and rectifier21. A filter condenser 28 across the rectifier output terminalsmaintains a substantially constant unidirectional current.

Referring further to Figure 4, the vehicle responsive device X of phaseB when actuated closes a circuit from L3 through leads 51, 57a toenergize a polarized relay PM permanently connected to L4 by lead 58. Alocking-in circuit through lead 511), armature 33 of the polarizedrelay, and lead 59, which will subsequently be traced to L3, continuesto supply power to the polarized relay PM after actuation of device Xhas energized it, and thus in effect the demand of a traversing vehiclefor right of way is stored.

The polarized relay PM is very high speed in its operation and for thisreason it can be energized by actuations of short duration. A relay M ofslower action is placed in parallel with the polarized relay PM acrossleads 51a and 58, and when energized it closes by means of its armature34 a circuit from L3 to lead 60a. Since in this embodiment there are notrafllc responsive devices for the pedestrian phase, in the phase P unitof the control apparatus as shown in Figure '7, L3 is connectedpermanently to lead 60.

Each timer unit of the control mechanism includes a motor 44 whichpreferably may be of the self-starting.synchronous type, and which maybe energized by alternating current from terminals Ll, L2. The motordrives a camshaft 46 on which are mounted a number of cams, cams Cl, C2,C3, C4, C5 and C6, each one of which operates a control circuit by meansof camsprings. The cams may be cut into the required shapes .fromcircular discs of suitable material, and mounted firmly on the camshaft.

The cams on the camshaft may be divided into a number of sections orpositions; in the embodiment shown there are twelve equal sectors orpositions to each cam, yet any greater or lesser number may be used.When the camshaft revolves into position I cam C| closes the lockingincircuit for the motor from LI to lead 5|b and 5| and retains thiscircuit closed until the cams rotate to their starting position,position zero or I2. The motor, once having been energized, thuscontinues to receive power for the duration of one complete revolutionof its camshaft, and then, in order to continue revolving or to restart,must be supplied power from another circuit. A locking-in circuit forthe polarized relay PM thru leads 59, 59a, is completed by cam C3 inpositions I, 3, 5, I, 9, H), II and I2 or 0, and interrupted forde-energizing this relay in positions 2, 4, 6 and 8.

l A right of way controlling relay SM is permanently connected to L4 bylead 2|] and may be energized for according right of way to lane B byconnection to L3 thru lead 6|, camsprings of cam CZ which are closedonly in position I, leads 60, 60a and armature 34 of relay M, energized.Relay SM may be locked-in by a circuit thru leads 6|a, armature 35, lead62, camsprings of cam C5 which are closed in all positions exceptposition It], lead 50b, and to L3 over camsprings of cam C4 which areclosed. in positions 2, 4, B, 8, l3, and II, and open in all otherpositions. Another lock-in circuit for relay SM is furnished by wire 60from wire 60a and armature 34 of relay M to L3. When relay SM is in itsde-energized position, alternating current from LI may be connected thrucamsprings of cam C6, which are closed in positions 2 thru inclusive,lead 54, armature 38 in its de-energized position, out of the unitillustrated as the phase B unit, and into the unit of the phase next insequence in the testing cycle, for example, phase C, and thru lead 5|therein to energize the motor 44 of the phase C unit.

In the de-energized position of relay SM, armature 31 completes anotherlocking-in circuit for the polarized relay PM thru lead 59 to L3. Thiscircuit parallels the locking circuit for the same relay over camspringsof cam C3 described above. When right of way controlling relay SM isenergized, its armature 31 completes a circuit to energize a right ofway signal transferring relay IM over lead 63.

The function of the right of way transferring relay IM in each unit isto govern change of the indications of the traffic signals in the lanecontrolled by the said unit. The relay IM for each of the several phasesis positioned in the control mechanism adjacent to the corresponding IMrelays of other phases in such a manner that a common tongue T operatesto lock-in the armature 38 of any IM relay upon energization of thelatter. An illustration of this portion of the apparatus by which anyone of armatures 38 of the several IM relays may be locked in itsenergized position by a common tongue T is shown in Figure 8. Thearmature of relay IM in each the units is permanently connected to Ll.In its energized position it engages leads 53, and 53a. and in its outor de-energized position, leads 52 and 52a.

When the IM relay of one phase unit, for example the phase B unit, isenergized, and its armature thereby attracted, the movement of thisphase B armature 38 into its energized position depresses a catch at theend of tongue T and releases the armature 38 of the relay IM of anyother phase which was at that time being lockedin by the tongue. Ihespring 39 quickly restores tongue T into its locking position where thetongue now holds the phase B armature 38 in its energized position, inwhich the said armature completes a circuit from LI thru lead 53 toenergize retarded pick-up relay MG of the B phase unit and thru lead 53ato supply power for the signal lights. In the A, C, and. P phase units,the armature 38 will now engage leads 52a and 52, whereupon a retardedpick-up relay MR in each of these units will be energized thru lead 52.

Considering again the phase B unit of the control mechanism, the inwardor rising movement of the armatures 40, 4| of the retarded pick-uprelays MG and MR is slow. A single pole double throw switch El isarranged to be operated by armature 4| of relay MR, as said armature 4|nears its inner, or energized, position. When the armature 4| of relayMR is in its innermost po sition, the end of said armature presses thearmature 43 of switch E|, into its upper position where it engages lead55. When armature 4| of relay MR is in any other but its innermostposition, the armature 43 of switch EI engages its lower contact 54.Although the armature of relay MR is slow to rise and requires anappreciable period to proceed from its de-energized or outer position toits inner position, the time required between the breaking of thecircuit from armature 43 to lead 54 and the making of the circuit tolead 55 is negligible, because of the proximity of the contacts at theends of leads 54 and 55. Armature of relay MG is similarly co-operablewith switch E2 which is similar to switch El.

Green signal G is illuminated when the armature 40 of relay MG is in itsinnermost position holding armature 42 in its upper position where thelatter completes a circuit from Ll, armature 38 thru lead 53a, armature42, lead 55, green signal G, to L2. Likewise red signal R is illuminatedWhen armature 455 is held in its upper position by armature 4| of relayMR, completing the circuit from Ll, over armature 38, lead 52a, armature43, lead 55, red signal R, to L2. Yellow or caution signal Y may beilluminated by either of two circuits from L! and armature 38; one overlead 53a, armature 42 in its lower position, and lead 54, the other overlead armature 43 in its lower position, and then over lead 54, yellowsignal Y to L2.

Referring to the phase B unit in Figure 4 again, relay K is placed inparallel with synchronous motor 44 between lead 5| and terminal L2;consequently relay K is energized whenever the motor 44 receives power.Now referring to Fig ure 5, a series starting circuit from A. C. powerterminal Ll thru armature 45 of relay K in the phase B unit and a backcontact S2 co-operating therewith, extends in series thru correspondingarmatures and contacts in the phase C and P units to lead 5i in thephase A unit. This circuit is closed to supply power to the motor ofphase A unit at such times as the motors in the several units are all intheir rest positions. Ordinarily the phase A unit will be started byenergization of its motor over cam springs of cam C6, lead 5 andarmature 36 of relay SM in the preceding phase P or pedestrian unit andover lead [5 to lead 5| of the phase A unit as will be subsequently morefully described, but the series starting circuit controlled by therelays K is provided as an independent means for starting the phase Aunit motor when all the units are in their zero or rest position and theordinary starting circuits via cam C6 are all interrupted, as mightresult, for instance, from having the power shut 01f in such fashion asto allow one or more of the camshafts to revolve by their own momentuminto the zero position. Any unit might be chosen as the starting unitinstead of the phase A unit, but in each case the starting unit needhave no relay K.

Operation of this traffic control system through one complete cycle ofthe control mechanism will now be described. Assume that there are novehicles approaching the intersection on any of the lanes and that thegreen signal G on the pedestrian phase and the red signals on phases A,B, and C are illuminated. A cycle of control commencing with phase Awill be described.

In the phase A, B, and C units, armature 38 of relay IM is in itsde-energized position. The MR. relay in each of these units is thusenergized from L! thru lead 52. Thru lead 52a, armature 43, and lead 55,in the manner aforedescribed, the red or stop signal R is illuminated onlanes A, B, and C. In the phase P unit armature 38 of relay IM is heldlocked in by tongue T, and the circuit to energize relay MG is completedthru lead 53. Consequently on the pedestrian phase P, green signal Gwill be energized by a circuit from Ll thru armature 33 of relay IM,lead 53a, armature 22, lead 56 to signal G and L2.

The motors of all the units of the control apparatus for thisillustration are assumed to be de-energized and for this reason theseveral relays K are also not energized. Upon connecting proper powersupply to Ll, L2, either the motor of one of the units, (A phase forinstance) is started over armature 36 of relay SM and camsprings of camC6 of the preceding phase unit P phase, for instance), or in the eventthat all of the cam groups are in their zero positions, the seriesstarting circuit from L! thru the armature 45 and the back contacts S2of the relays K of units B, C, and P energizes the motor of the; phase Aunit thru lead 5!. The motor will thus be started and maintainedenergized in either one fashion or the other described until in positioni its associated cam Ci closes a circuit to energize the motorindependently of the starting circuit for the balance of its camshaftcycle. Also in position i cam C2 closes its contact to prepare orpartially complete an operating circuit for relay SM via wire 6| to wire6!] and via wire 53a to the contact associated with armature 34 of relayM. This action of cam C2 thus in effect potentializes relay SM foroperation to cause transfer of right of way through energization ofrelay IM in event relay M has been energized by traffic actuation asalready described. After the cam shaft has passed position I the cam Ci?breaks this preparatory circuit for relay SM and the relay cannot beenergized through the remainder of one revolution of the cam shaft. Whenrelay SM is deenergized it cannot operate the relay IM to transfer rightof way and it may thus be considered depotentialized by action of cam C2in opening its preparatory circuit. The cam 02 may thus be considered topotentialize relay SM for right of way transfer in position i and todepotentialize it in position 2 and other positions. In the presentinstance it was assumed there was no trafiic actuation on phase A andrelay SM remains deenergized as the cams turn in to position 2. Inposition 2, cam C6 completes over its camsprings the circuit from LIthru lead 6 armature 35 oi": relay SM which remains de-energized in theabsence of actuation as assumed, to energize thru lead 5| the motor M.of the next phase in the sequence, phase B, and this motor commences torevolve in the manner just described. In position l2 of the phase A unitcamshaft, power is disconnected from the phase A unit motor by cam Cland the camshaft rests in this position. Power is also disconnected fromthe feed circuit to phase B unit at cam C6. Phase B unit motor 44,however, continues to revc-lve, since it now receives powerindependently thru its lead 5H), from its own cam Cl camsprings.

The phase B unit in position 2 in its cycle by cam C6 similarlyenergizes the motor of the phase C unit, which also commences to operatein a manner similar to that of the phase A and B units. There have beenno signal changes or changes in the relays in the several units of thecontrol mechanism, excepting the starting circuit embracing the relays Kwhich are energized when their respective motors are energized, thecondition of the several r maining circuits being as described at thestart of the control cycle. Since there have been no actuations of thevehicle responsive devices in any of the several lanes the relays M, SM,and IM of each unit will remain de-energized.

Considering further the control mechanism cycle, when the camshaft ofphase C unit reaches position 2, the phase P unit motor is started andthe independent power circuit over camsprings of cam Cl is closed. Aspointed out above and shown in Figure 7, the pedestrian or phase P unitin one embodiment has no pedestrian actuatable device and associatedrelays PM and M, and in this case lead 60 is permanently connected toL3. In position I of the phase P unit, its cam C2 closes the circuitfrom L3 thru leads 60, BI to energize right of way controlling relay SM,which locks-in over lead 61a, armature 35, lead 62, camsprings of camC5, lead 60 to L3. Armature 31 completes a circuit from L3 thru lead 63to energize right of way transferring relay IM. Since green is beingdisplayed to phase P, as already described, the armature 38 of relay IMof phase P is already locked-in in its ener gized position by tongue T,thus no change in the energization of the signals will occur, and greenwill persist on the pedestrian phase. Cam C2 in position 2 has openedthe circuit between leads 60 and SI which originally energized the SMrelay, but this relay remains energized by its lock-in circuit thru itsarmature 35, leads 62, 60, to L3.

At position 2 cam C6 prepares a circuit from terminal Ll to lead 64, forenergizing the motor of the succeeding phase unit (phase A), but theenergized condition of relay SM prevents the circuit from beingcompleted at armature 36 until the camshaft revolves to position wherecam C5 opens the locking-in circuit for relay SM between leads 62 and 60and de-energizes relay SM. In position 18, therefore, armature 36assumes its de-energized position, and thus the circuit for starting themotor of the next unit, phase A, is completed from Ll over thecamsprings of cam C6, lead 64, armature 36 of relay SM and lead i5 inthe phase P unit to lead 5! and motor 44 of the phase A unit, as shownin Figure 5. With relay SM energized from position 2 to position I!) asdescribed, its contact and armature 36 remain separated and prevent theenergization of the next (phase A) unit motor and thereby assuremaintenance of the pedestrian phase right of way during this time.Change'of right of way can only occur by energization of the IM relay ofanother phase and this can only occur at position I in the cycle of thecamshaft of another phase after the motor of that phase has'beenenergized over armature 36 of relay SM and contacts of cam C6 of thepreceding phase unit as described above.

. If now it is assumed a vehicle has passed over the actuable device Xin the lane A, a circuit thru device X from L3 thru leads 51, 51a, willenergize relay PM, which looks in over lead 51b, its own armature 33,leads 59, 59a, springs of cam C3, to L3. Slower acting relay M, inparallel across leads 51a and 58, is also energized and maintainedenergized with relay PM by the lock-in circuit for the latter justdescribed and by means of its armature 34, relay M closes a circuit fromL3 to lead 68a. The phase A unit motor, started by the circuit fromarmature 36 of the phase P unit, receives power during its cycle by thecircuit to Ll thru camsprings of camCl. In position I cam C2 againcloses the circuit from lead 60 to 6| to test for a demand for right ofway. Since an actuation has locked in relay M and connected lead 60 toL3 over armature 34, relay SM is energized and is locked in over lead 6la, armature 35, lead 62, camsprings of cam C5, lead 60, then inposition I over lead 60a, armature 34 of relay M to L3, and in position2 over lead 607), camsprings of cam C4 to L3. In position 2 thelocking-in circuit for relays PM and M is broken by operation of cam C3.

In the manner described above for the phase P unit, the energization ofrelay SM causes power to be supplied over armature 31 and lead 63 torelay IM which attracts its armature 38. As the armature 38 of relay IMin the A phase unit moves into itsenergized position, it depressestongue T common to all the units and releases the armature 38 of thephase P unit which was being locked-in. Thus in the phase P unit,circuit from LI' and armature 38 to leads 53 and 53a is thereby brokenand circuit to leads 52 and 52a is made. When the armature 38 breaksfrom lead 53, the relay MG is de-energized, and at the same time, bybreaking the circuit from the armature 38 to lead 5317., the greensignal G is extinguished. The armature 38 immediately completes acircuit over lead 52a, armature 43, which is in its lower position, lead54, to illuminate the yellow signal Y. Simultaneous with completion ofthis'circuit, the same armature completes a circuit over lead 52 toenergize the retarded pick-up relay MR, which slowly attracts its armature. The yellow signal Y persists during the time required forarmature 4| of relay MIR to rise from its out or de-energized positionuntil armature 4| causes armature 43 of switch El to break circuit withlead 54. When armature 43 of switch El makes circuit with lead 55, thered signal R is illuminated.

Meanwhile the signals to phase A change from red to yellow to green. Inthis case armature 38 of relay IM in the phase A unit breaks circuitwith leads 52 and 52a de-energizing the associated relay MR, and movesinto its energized position, as pointed out above, where Ll is connectedthru the armature 38 to leads 53 and 53a for energizing relay MG. Whenpower is disconnected from the lead 52a, red signal R to phase A isextinguished and when power is immediately thereafter connected to lead53a, yellow signal Y is energized over lead 53a, armature 42 of switchE2 and lead 54. Correspondingly when power is disconnected from lead 52,relay MR becomes die-energized, and when power is connected over lead 53to relay MG, the latter relay slowly attracts its armature 40. Yellowsignal Y persists until armature 40 causes armature 42 of switch E2 tobreak circuit with lead 54. Armature 42 then engages lead 56 completingthe circuit to illuminate green signal G on phase P. By adjusting thetime delay devices associated with the slowto-pull-in relays, theduration of the amber signal may be fixed as desired.

As the camshaft 46 of the phase A unit revolves, in position 2 cam C2operates to break the pull-in circuit of relay SM between leads 60 andBI. In position 2, cam C3 operates to open the lock-in circuit for relayPM and relay M, from lead 59a to L3, and these relays are therebyde-energized. Also in position 2, cam C4 makes a circuit from leads 62,60 to L3 maintaining relay SM locked-in. In the succeeding position,position 3, the cam C4 breaks this circuit and relay SM is de-energized.Relay IM thereupon is deenergized since armature 31 breaks circuit thrulead 63, but the armature 38 of relay IM remains locked-in by tongue T.Armature 36 completes the energizing circuit from Ll thru springs of camC6, leads 64, and to start the motor of the phase B unit.

Assume now that a vehicle has traversed the responsive device X in laneB. Polarized relay PM and relay M are energized in a manner similar tothat described above in connection with phase A, and the energization ofrelay SM when the phase B unit motor has rotated the camshaft intoposition I is likewise similar to the manner of operationaforedescribed. Signals change from green thru yellow to red for phase Aand from red thru yellow to green for phase B. Assume now that anothervehicle actuates the device X in lane B after cam C3 has opened andreclosed its camsprings in position 2 and before cam C4 opens itscamsprings in position 3. The actuation re-energizes and locks-in relaysPM and M over the circuits for this purpose already described.Accordingly, although a locking-in circuit from L3 to relay SM thrucamsprings of cam C4, leads 68 and 62 is opened by operation of cam C4during position 3, the relay is retained in its energized state by powerfrom L3 thru armature 34, leads 60a, 68 and 62. If there are no furtheractuations after cam C3 in position 4 opens the locking-in circuit tothe polarized relay PM and to relay M and until cam C4 opens itscamsprings in position 5, the operation of cam C4 will open theremaining locking-in circuit thru lead 62 for relay SM, which isthereupon de-energized. The motor of the phase C unit is then connectedto power in the manner aforedescribed.

Such factors as the speed of the camshaft,

shape of the cams, distance of the vehicle responsive devices from theintersection, and timing of the caution signal following green, or anyone or more of these or other factors, may be arranged to permit anyvehicles that actuate the responsive devices in a lane between theinitial actuation which secured transfer of right of way to the saidlane and the actuation which as described secured extension of right ofway to pass thru the intersection.

Should there have been a substantially continuous stream of traffic onlane B, such that vehicle responsive device X in that lane had beenactuated and relay PM again locked-in after cam 03 had broken itslocking-in circuit in position 4 and before relay SM became de-energizedin position 5, relay SM would have remained energized until position I,and with similar additional vehicular actuation at the end of position 6would have remained energized until position 9, as will be apparent withan examination of the shape of cams C3 and C4 in Figure 4, in View ofthe foregoing description. If actuations continue to keep relay PMenergized, right of Way will be forcibly removed from phase B inposition Ill where cam C5 operates to break the locking-in circuit toright of way controlling relay SM between leads 60 and 62. Oncede-energized, the relay SM in any unit cannot again be energized untilthe camshaft reaches position I, in the succeeding cycle of operation ofthe unit.

An actuation of the responsive device in any phase, after relay SM forthat phase has been de-energized, will energize relay PM in thecustomary manner and will lock it in with relay M over lead 59 andarmature 31 to L3. Similarly, if actuation occurs in any phase while itscam shaft is rotating and has passed position i and is in anintermediate position when that phase does not have right of way, suchactuation will occur with relay SM in its deenergized position, andrelays PM and M will become energized by such actuation and be locked inover armature 31 of relay SM as just described. Such late actuatio-nswill thus in effect be stored, until the camshaft in that phase unit isagain started from its rest position. Since in either case after the camshaft has passed position I, the initial energizing circuit for relay SMand operated by cam C2 is kept open as the cam shaft continues torotate, the relay SM remains in its deenergized position keeping therelays PM and M locked in. If the actuation was too late to energizerelay SM in position I right of way will not be transferred to thisparticular phase during this cycle of rotation of its cam shaft, but inposition 2 the cam C6 will operate to close the circuit over a wire 64and via armature 36 of relay SM to start the cam shaft of the next phaseinto rotation as has been already described, and both the next phase camshaft and the current phase cam shaft will continue to rotate back totheir initial rest positions 0. The cam shaft of the current phase, onwhich the late actuation occurred, is again initiated into activity byaction of the cam shaft of the preceding phase in the manner alreadydescribed. As the camshaft again becomes activated and revolves intoposition I, testing for actuation, a circuit embracing relay SM will becompleted between L4 and L3 thru relay SM over lead Bl, camsprings ofcam C2, leads 60, 60a, and armature 34 of relay M in its energizedposition. Relay SM is thereby energized and obtains a transfer of rightof way in favor of the waiting vehicle. The locking-in.

circuit for the relays PM and M over lead 59 and armature 31 to L3 isbroken upon the energize.- tion of relay SM.

The term timer is used herein for a device operating at a certain timerate, which may be adjustable, and which in its course of operationopens and closes or otherwise controls a series of electric circuits inpredetermined time relation. In this application the timer isillustrated for example as a motor-driven series of cams with theirassociated contacts. In certain of the claims the SM relay is recited aspart of the timer. As already described one such timer, including thecam shaft and contacts, driving motor and the SM relay, preferably isprovided for each street or lane to which right of way is separatelygiven in association with a mechanism for transferring the right of Wayto and from that lane. In this respect the several timers for theseveral lanes are designated as unit timers. These timers are. eacharranged to be operated from an initial position thru their sequence ofcircuit controlling functions and returned to such initial position fromwhich they can again repeat such operation. The timer in operating thruone such sequence of functions from initial position and returning toinitial position is recited in the claims as operable in a time cycle.

The term mutually interfering lanes as used herein designates aplurality of lanes of traffic movement each of which intersects all theothers or in which the traffic movement interferes with trafiic movementof the others. For example, in the case of three. mutually interferinglanes each of the lanes interferes with the other two. The term lane asused herein does not necessarily mean a single path for traffic movingin one direction but is used to designate one or more lanes which aresignalized as a unit. For example, the pedestrian phase alreadydescribed may be considered a single interfering lane although itcomprises several pedestrian paths crossing different parts of theintersection which are signalized as one unit and pedestrian movement insome one of these paths would normally interfere with other trafficmovement.

As previously mentioned, pedestrian push buttons or other actuatabledevices may be used in the pedestrian phase in the same manner in whichvehicle responsive apparatus is employed in the vehicle phases. In thiscase right of way is not transferred to the pedestrian or P phase eachtime this phase is tested, as in the embodiment described, but only whenactuation of the responsive device has locked-in the relay M in thisphase with which the apparatus is then provided. The green signal G inthis phase will be displayed for a minimum or greater period dependingupon trafiic actuations as explained above in connection with operationof the vehicular phase units A, B, or C.

It will be understood that themotors in the several phase units may beequipped with speed adjusting devices in order that by presetting thespeeds of the several motors differences in the time required forvehicles on different lanes to pass thru the intersection afteractuating their respective responsive devices, and other factors, may betaken into account. It may also be desirable to have a greater or lessnumber of projecting points on the cams C3 and 04 for example, in orderto provide more or fewer potential right of way extension periods on oneor more of the intersecting lanes.

The terminals L3, L4 of the direct current power for operating relays inthe several units are labelled for the sake of simplicity of descriptiononly and either the L3 pole or the L4 pole shown in the drawings mightbe grounded. Alternating current relays might be used in lieu of thoseoperating from direct current.

Numerous other changes in the structure or design of a traffic controlsystem of the character shown in this specification, as the substitutionof static timing devices of the retarded pick-up relay timers, or otherchanges, might be mad-e without departing from the spirit of theinvention as defined by the claims.

Having described our invention what we claim as new and desire to secureby Letters Patent of the United States is as follows:

1. A traffic signal control apparatus for mutually interfering trafficlanes including right of way transferring mechanism for controllingsignals to accord and interrupt right of way on the said lanes, trafficactuatable means for each lane, control means associated with each laneand operating solely in response to actuation of the actuatable means inthat lane to cause only when potentialized said right of waytransferring mechanism to accord right of way to the said lane, timingmeans continuously operating for normally cyclically and successivelypotentializing and depotentializing said control means for each lane,

- and means for delaying said cyclic potentializing upon such accord ofright of way to any of the lanes.

2. A traffic signal control apparatus for mutually interfering trafficlanes including control mechanism for said signal and comprising anindividual right of way transferring mechanism for each lane, in eachlane a traffic actuatable device operable upon actuation by traffic topotentialize the right of way transferring mechanism associatedtherewith to accord right of way to the lane of the actuation, timingmeans continuously operating to cause cyclically one at a time the rightof way transferring mechanisms only when potentialized to accord rightof way to the lane of the mechanism, and means for delaying such cyclicoperation of the timing means upon accord of right of way to any of thelanes.

3. A traffic control system for the intersection of a plurality ofmutually interfering trafiic lanes having a signal for displaying rightof way according and interrupting indications in said lanes, a trafficactuatable device in each lane, a control mechanism for said signal andcomprising an individual right of way transferring mechanism associatedwith each lane and connected to the traflic actuatable device therein, atiming means operating continuously cyclically to potentialize anddepotentialize successively one right of way by the latter transferringmechanism at a time for transferring right of way to the lane associatedtherewith solely when so potentialized and rendered operable in responseto actuation of its actuatable device, means operating upon suchtransfer of right of way to one lane to delay progress of the cyclicoperation of the timing means for at least a minimum time period andmeans associated with each right of way transferring mechanism formantaining the display of the signal upon such transfer of right of wayto one lane until any other right of way transferring mechanism isrendered operable in response to actuation of its actuatable device.

4. A trafiic controt system for a plurality of mutually interferingtraffic lanes including in combination, traffic actuated meansassociated with and individual to each lane, and one for each lane of aplurality of right of way signalling means, a plurality of right of waytransferring mechanisms therefor, and a plurality of timers, each timerwhen activated operable thru a time cycle and connected to the right ofway transferring mechanism and to the traffic actuated means for itslane and including means acting upon actuation of such traffic actuatedmeans to cause accord of right of way to such lane by the transferringmechanism thru the signalling means in a part of such cycle and meansforming a part of each timer and operable at a predetermined point inthe time cycle of the same to activate another of said timers wherebysuccessive operation of the timers occurs in predetermined sequence.

5. A traffic control system for a plurality of mutually interferingtrafiie lanes including in combination, traffic actuated meansassociated with and individual to each lane, and one for each lane of aplurality of right of way signalling means, a plurality of right of Waytransferring mechanisms therefor, and a plurality of timers, each timerwhen activated operable thru a time cycle and connected to the right ofway transferring mechanism and to the traflic actuated means for itslane and including means acting only in a predetermined part of the timecycle of said timer upon actuation of such traffic actuated means toaccord right of way to such lane and means forming a part of each timerand operable in a further part of the time cycle of the same to activateanother of said timers whereby successive operation of the timers occursin predetermined sequence.

6. A trailic control system for a plurality of mutually interferingtraffic lanes including in combination, traffic actuated meansassociated with and individual to each lane, and one for each lane of aplurality of right of way signalling means adapted to accord andinterrupt right of way, a plurality of right of way transferringmechanisms therefor, and a pl rality of timers, each timer whenactivated operable thru a time cycle and connected to the rig t of waytransferring mechanism and to the traffic actuated means for its laneand including means acting upon actuation of such trafiic actuated meansto cause accord of right of way to such lane by the transferringmechanism thru the signalling means in a part of such cycle andinterlocking means for said plurality of right of way trans ferringmechanisms whereby accord of right of way to any one lane causesinterruption of right of way in the other lanes, and means forming apart of each timer and operable at a predetermined point in the timecycle of the same to activate another of said timers whereby successiveoperation of the timers occurs in predetermined sequence.

7. A trafiic control system for a plurality of mutually interferingtraffic lanes including in combination, traflic actuated meansassociated with each lane, right of way signalling means for the lanes,right of way transferring mechanism therefor, and a plurality ofindividual unit timers one for each lane, each timer when activatedoperable thru a time cycle and connected to its associated trafficactuated means and to the right of way transferring mechanism, eachtimer including control means operable in one part of its time cycle tocause right of way transferring mechanism to accord right of way to thelane associated with such timer in response to actuation of the tramcactuated means in such lane, and means operable in a further part of itscycle to activate another unit timer whereby successive operation of theunit timers in sequence occurs and means associated with said right ofway transferring mechanism for maintaining it in the position to whichit was last operated by one control means until operated by anothercontrol means whereby through said signalling means right of Way will bemaintained on any lane to which it is accorded until the control meansin the timer of another lane is operated.

8. A trafiic control system for a plurality of mutually interferingtraffic lanes including in combination, traffic actuated meansassociated with each lane, and one for and individual to each lane of aplurality of right of way signalling means for according andinterrupting right of way therein, a plurality of right of waytransferring mechanisms therefor, and a plurality of unit timers, eachright of way transferring mech anism having an element movable from anormal position in which right of way is interrupted in its associatedlane to an operated position in which right of way is accorded to itsassociated lane, each timer connected to the right of way transferringmechanism and to the traffic actuated means for its lane and includingmeans acting only when its unit timer is operative and upon actuation ofthe traffic actuated means to operate such transferring mechanism andits movable element to cause accord of right of way to such lane for atime period, means interconnecting the several timers for rendering themindividually so operative in sequential order, and latching meansmechanically interlocking the movable elements of the plurality of suchmechanisms to maintain any such element so operated to continue accordof right of way to its lane beyond said time period and untilcorresponding operation of another such element and to cause by suchoperation by any such movable element in according right of way to onelane the concurrent restoration of the movable element of any othermechanism of the other lanes to normal whereby right of way ismaintained by any one element in its associated lane only and until itis interrupted by accord of right of way to another lane by another suchelement.

9. A traffic control system for a plurality of mutually interferingtraffic lanes including in combination, traffic actuated meansassociated with each lane, and one for and individual to each lane of aplurality of right of way signalling means, for according andinterrupting right of way thereon, a plurality of right of waytransferring mechanisms therefor, and a plurality of unit timers eachright of way transferring mechanism'having electro-magnetic meansincluding an armature movable from a normal position in which it causesinterruption of right of way in its associated lane to an operatedposition in which it causes accord of right of way to its associatedlane, each timer connected to the right of way transferring mechanismand to the traffic actuated means for its lane and including meansacting only when its unit timer is opera tive and upon actuation of thelast named traflic actuated means to operate such transferring mechanismand its movable armature to cause accord of right of way to such lanefor a time period, means interconnecting the several timers forrendering them individually so operative in sequential order, andlatching means mechanically interlocking the movable armatures of theplurality of such mechanisms to maintain any such armature so operatedto continue accord of right of way to its lane beyond said time perioduntil corresponding operation of another such armature and to cause bysuch operation of any such movable armature in according right of way toone lane the concurrent restoration of the movable armature of any othermechanism of the other lanes to normal whereby right of way ismaintained by any one armature in its associated lane only and until itis interrupted by accord of right of way to another lane by another sucharmature.

10. A traffic control system for a plurality of mutually interferingtraffic lanes including in combination, traffic actuated meansassociated with each lane, and one for and individual to each lane of aplurality of right of way signalling means adapted to accord andinterrupt right of way, a plurality of right of way transferringmechanisms therefor and each adapted when operative to cause accord ofright of way to its respective lane and to maintain such right of wayuntil interrupted by transfer of right of way to another lane by thetransferring mechanism of the latter lane, and a plurality of timers,each timer when activated operable through a time cycle and connected tothe right of way transferring mechanism and to the traffic actuatedmeans for its lane and including means acting only in a predeterminedpart of the time cycle of said timer upon actuation of such trafiicactuated means to accord right of way to such lane through its connectedtransferring mechanism, means interconnecting said plurality ofmechanisms to cause interruption of right of way in the other lanes uponsuch accord of right of way to any one such lane, and means forming apart of each timer and operable at a predetermined point in the timecycle of the same to activate another of said timers whereby successiveopera-- tion of the timers occurs in predetermined sequence.

11. A traflic control system for a plurality of mutually interferingtraffic lanes including in combination, trafiic actuated meansassociated with each lane, and one for and individual to each lane of aplurality of right of way signalling means adapted to accord andinterrupt right of way, a plurality of right of way transferringmechanisms therefor and each adapted when operated to cause accord ofright of way to its respective lane and to maintain such right of wayuntil interrupted by transfer of right of way to another lane by thetransferring mechanism of the latter lane, and a plurality of timers,each timer when activated operable through a time cycle and having acircuit for connecting it to the right of way transferring mechanism andto the traflic actuated means for its lane and including means operablein one part of the time cycle of said timer to partially complete saidcircuit for effecting operation of the right of way transferringmechanism, and means operable responsive to actuation of said traflicactuated means to complete said circuit, whereby said right of waytransferring mechanism will be operated to transfer right of way to itscor responding lane through its connected transferring mechanism, meansinterconnecting said plurality of mechanisms to cause interruption ofright of way in the other lanes upon such accord of right of way to anyone such lane, and means forming a part of each timer and operable at af predetermined point in the time cycle of the same to activate anotherof said timers whereby successive operation of the timers occurs inpredetermined sequence.

12. A traffic control system for a plurality of mutually interferingtraffic lanes including in combination, trafiic actuated meansassociated with and individual to each lane, and one for each lane of aplurality of right of way signalling means, a plurality of right of waytransferring mechanisms therefor, and a plurality of timers, each timerwhen activated operable thru a time cycle and having a circuit forconnecting it to the right of way transferring mechanism and to thetraffic actuated means for its lane and including means operable in onepart of the time cycle of said timer to prepare said circuit foreffecting operation of the right of way transferring mechanism, andmeans operable responsive to actuation of said traflic actuated means tocomplete said circuit whereby said right of way transferring mechanismwill be operated to transfer right of way to its corresponding laneduring such part of such cycle, means forming a part of said timer andoperating in a further part of the time cycle to activate another ofsaid timers whereby successive operation of the timers occurs in apredetermined sequence.

13. A traffic control system for a plurality of mutually interferingtraffic lanes including in combination, traflic actuated meansassociated with and individual to each lane, and one for each lane of aplurality of right of way signalling means, a plurality of right of waytransferring mechanisms therefor and each adapted when operated to causeaccord of right of way to its respective lane and to maintain such rightof way until interrupted by transfer of right of way to another lane bythe transferring mechanism of the latter lane, and a plurality oftimers, each timer when activated operable thru a time cycle and havingacircuit for connecting it to the right of way transferring mechanism andto the traffic actuated means for its lane and including means operablein one part of the time cycle of said timer to prepare said circuit foreffecting operation of the right of way transferring mechanism, andmeans operable responsive to actuation of said traffic actuated means tocomplete said circuit whereby said right of Way transferring mechanismwill be operated to transfer right of way to its corresponding laneduring such part of such time cycle, means forming a part of said timerand operating in a further part of the time cycle to activate another ofsaid timers whereby successive operation of the timers occurs inpredetermined sequence, means associated with the said timer andoperable upon such actuation of the traflic actuated means of its laneto delay operation of said activating means for a time period wherebyright of way will be maintained on such lane for at least a minimumperiod before transfer of right of way by another timer and associatedright of way transferring mechanism to the lane of the latter, cancorrespondingly be effected.

14. A traffic control system for a plurality of mutually interferingtraiiic lanes including in combination, trafiic actuated meansassociated with and individual to each lane, and one for each lane of aplurality of right of way signaling means, a plurality of right of waytransferring mechanisms therefor and each adapted when operated to causeaccord of right of way to its respective lane and to maintain such rightof way until interrupted by transfer of right of way to another lane bythe transferring mechanism of the latter lane, and a plurality oftimers, each timer when activated operable thru a time cycle and havinga circuit for connecting it to the right of way transferring mechanismand to the traffic actuated means for its lane and including meansoperable in one part of the time cycle of said timer to prepare saidcircuit for effecting operation of the right of Way transferringmechanism, and means operable responsive to actuation of said trafiicactuated means occurring prior to said one part of the cycle to completesaid circuit in said one part whereby said right of way transferringmechanism will thereupon be operated to transfer right of way to itscorresponding lane, means forming a part of said timer and operating ina further part of the time cycle to activate another of said timerswhereby successive operation of the timers occurs in predeterminedsequence, means associated with said timer and operable upon furtheractuation of the traffic actuated means of its lane while right of wayis accorded to such lane to delay operation of said activating meanswhereby the maintaining of right of way on said lane will be prolonged,and further means associated with each timer to provide a maximum limitto such prolongation by a plurality of such further actuations.

15. A trafllc control system for a plurality of mutually interferingtraiiic lanes including in combination, trafiic actuated meansassociated with and individual to each lane, and one for each lane of aplurality of right of way signalling means, a plurality of right of waytransferring mechanisms therefor, and a plurality of timers, each timerwhen activated operable thru a time cycle and having a circuit forconnecting it to the right of way transferring mechanism and to thetraffic actuated means for its lane and including means operable in onepart of the time cycle of said timer to prepare said circuit foreffecting operation of the right of way transferring mechanism, andmeans operable responsive to actuation of said trafiic actuated meansoccurring prior to said one part of the cycle to complete said circuitin said one part whereby said right of way transferring mechanism willthereupon be operated to transfer right of way to its correspondinglane, means forming a part of said timer and operating in a further partof the time cycle to activate another of said timers whereby successiveoperation of the timers occurs in predetermined sequence, meansassociated with each said timer and operable upon further actuation ofthe traflic actuated means of its lane while right of way is accorded tosuch lane to delay operation of said activating means whereby the rightof way on said lane will be prolonged. before transfer can be effectedto another lane in response to actuation in the latter, and furthermeans associated with said timer to cause activation of another timerafter a maximum period of such delay by a plurality of such actuationsand independently of said delaying means.

16. A traflic control system for a plurality of mutually interferingtraffic lanes including in combination, traffic actuated meansassociated with each lane, right of way signalling means for the lanes,right of way transferring mechanism therefor, and a plurality ofindividual unit timers one for each lane, each timer when activatedoperable thru a time cycle and connected to its associated trafficactuated means and to the right of way transferring mechanism, eachtimer including control means operable in one part of its time cycle tocause said right of way transferring mechanism to accord right of way tothe lane associated with such timer in response to actuation of thetraffic actuated means in such lane, and means operable in a furtherpart of its cycle whose time relation to said one part of such cycledepends on further actuations during such cycle to activate another unittimer whereby successive operation of the unit timers in sequenceoccurs.

17. Traflic signal control apparatus for mutually interfering trafiiclanes including in combination, right of way transferring mechanism forcontrolling right of way signals to accord and interrupt right of Way inthe lanes, traffic actuated means for each lane, and a plurality ofindividual unit timers, one for each lane, and each connected to thetraffic actuated means for its lane and connected to said mechanism,each timer comprising a camshaft when activated operable thru a cycle,cams mounted on said camshaft, switches operated by said cams, camshaftdriving means, and relay means operated from an unoperated position toan operated position by one of said switches in a predetermined part ofthe cycle of said camshaft upon actuation of the corresponding trafficactuated means to operate said transferring mechanism to accord right ofway to the lane of such corresponding traffic actuated means and meansoperated by said relay means in its unoperated position and incooperation with operation of another of said switches in a further partof the camshaft cycle to activate another of said timers wherebysuccessive operation of the plurality of timers in sequence occurs. V

18. Traffic signal control apparatus for mutually interfering trafiiclanes including in combination, right of way transferring mechanism forcontrolling right of way signals to accord and interrupt right of way inthe lanes, trafiic actuated means for each lane, and a plurality ofindividual unit timers, one for each lane, and each connected to thetraffic actuated means for its lane and connected to said mechanism,each timer comprising a camshaft when activated operable thru a cycle,cams mounted on said camshaft, switches operated by said cams, camshaftdriving means, and relay means operated from an unoperated position toan operated position by one of said switches in a predetermined part ofthe cycle of said camshaft upon actuation of the corresponding trafficactuated means to operate said transferring mechanism to accord right ofway to the lane of such corresponding traffic actuated means and meansoperated by said relay means in its unoperated position and incooperation with operation of another of said switches in a further partof the camshaft cycle to activate another of said timers wherebysuccessive operation of the plurality of timers in sequence occurs andmeans operated by further actuation of said traffic actuated means whensaid relay is operated to maintain it in operated position whereby saidaction of said activating means is delayed and right of way prolonged onthe lane of said traflic actuated means.

19. Trafiic signal control apparatus for mutually interfering trafficlanes including in combination, right of way transferring mechanism forcontrolling right of way signals to accord and interrupt right of way inthe lanes, traffic actuated means for each lane, and a plurality ofindividual unit timers, one for each lane, and each connected to thetraffic actuated means for its lane and connected to said mechanism,each timer comprising a camshaft when activated operable thru a cycle,cams mounted on said camshaft, switches operated by said cams, camshaftdriving means, and relay means operated from an unoperated position toan operated position by one of said switches in a predetermined part ofthe cycle of said camshaft upon actuation of the corresponding trafficactuated means to operate said transferring mechanism to accord right ofway to the lane of such corresponding traffic actuated means at least aslong as said relay means is in its operated position, and means operatedby said relay means in its unoperated position and in cooperation withoperation of another of said switches in a further part of the camshaftcycle to activate another timer whereby successive operation of theplurality of timers in sequence occurs, means operated by actuation ofsaid traffic actuated means when said relay means is operated tomaintain it in operated position for a time period whereby said actionof said activating means is delayed and right of way prolonged on thelane of said tramc actuated means and means including a third one ofsaid switches for preventing said relay means from remaining in itsoperated position for more than a predetermined maximum portion of thecamshaft cycle.

20. Traific signal control apparatus for mutually interfering trafiiclanes including in combination, right of way transferring mechanism forcontrolling right of way signals to accord and interrupt right of way inthe lanes, traffic actuated means for each lane, and a plurality ofindividual unit timers, one for each lane, and each connected to thetrafiic actuated means for its lane and connected to said mechanism,each timer comprising a camshaft when activated operable thru a cycle,cams mounted on said camshaft, switches operated by said cams, camshaftdriving means, and relay means operated from an unoperated position toan operated position by one of said switches during a predeterminedportion of the cycle of said camshaft upon actuation of thecorresponding traffic actuated means to operate said transferringmechanism to accord right of way to the lane of such correspondingtraffic actuated means at least as long as said relay means is operated,means operated by said relay'means in its unoperated position and incooperation with operation of another of said switches in a further partof the camshaft cycle to activate another timer whereby successiveoperation of the plurality of timers occurs in sequence, means includinganother cam-operated switch operated upon actuation of saidcorresponding trafiic actuated means while said relay means is inoperated position to maintain it therein and thus extend its period ofoperation and consequently the right of way period on the lane of saidcorresponding trafiic actuated means for a further predetermined part ofsaid cam shaft cycle, and means including a third cam-operated switch toprevent said relay means from being maintained in operated position formore than a predetermined maximum portion of the camshaft cycle.

21. Traffic signal control apparatus for mutually interfering trafficlanes including in combination, right of way transferring mechanism forcontrolling right of way signals to accord and interrupt right of way inthe lanes, traflic actuated means for each lane, and a plurality ofindividual unit timers, one for each lane, and each connected to thetraffic actuated means for its lane and connected to said mechanism,each timer comprising a camshaft when activated operable thru a cycle,cams mounted on said camshaft, switches operated by said cams, camshaftdriving means, relay means operated from an unoperated position to anoperated position by one of said switches during a predetermined part ofthe cycle of said camshaft upon actuation oi the corresponding trafficactuated means to operate said transferring mechanism to accord right ofway to the lane of such corresponding traflic actuated means at least aslong as said relay means is in its operated position, means including asecond cam-operated switch to store the effect of actuation of thetrafiic actuated means in certain further parts of said camshaft cycle,means including a third cam-operated switch to maintain said relay meansin operated condition longer than for said predetermined part of thecamshaft cycle in response to operation of said last recited meansincluding the second switch, and means activated by said relay means inits unoperated position and in cooperation with operation of a fourthcam-operated switch in a still further part of the camshaft cycle toinitiate activation of another timer whereby successive activation ofthe plurality of timers in sequence is effected.

22. 'Iraffic signal control apparatus for mutually interfering trafficlanes including in combination, right of way transferring mechanism forcontrolling right of way signals to accord and interrupt right of way inthe lanes, means ineluding relays individual to the several lanes andoperated responsive to traiiic approaching in the respective lanes, anda plurality of unit timers, one for each lane, and each connected to thetrafiic responsive relay for its lane and connected to said mechanism,each timer comprising a camshaft when activated operable thru a cycle,cams mounted on said camshaft, switches operated by the cams, camshaftdriving means, relay means operated from an unoperated condition to anoperated condition by one of said switches during a predetermined partof the camshaft cycle upon actuation of the corresponding trafficresponsive relay to operate said transferring mechanism to accord rightof way to the lane of such corresponding trafiic responsive relay atleast as long as said relay means is in its operated position, meansincluding a second of said switches to lock-in the trafiic responsiverelay upon actuation thereof by trailic in certain positions of thecamshaft cycle and to maintain said relay means in operated condition insuch posi tions, means including a third of said switches to maintainsaid relay means in operated condition in other than said certainpositions of said cycle after the last named means has locked it in apreceding certain position, said cams arranged to render said last twonamed means Op rative alternately, and means operated by said relaymeans in its unoperated position and in cooperation with a fourth ofsaid switches in a further part of said camshaft cycle to initiateactivation of another timer whereby successive activation of theplurality of timers in sequence is efiected.

WILLIAM C. NEIN. THOMAS W. VARLEY.

CERTIFICATE OF CORRECTION.

Patent No. 2,1ll .,968. April 19, 1958. WILLIAM G. NEIN; ET AL.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows; Page 7first coiumn, line 59, claim 5, strike out the words "by the latter" andinsert the same after "way" in line 60, same claim; page? secondcolumn,- line 22, claim 1). before "timer" insert each; and line 28,same claim, before "each" insert said; and that the said Letters Patentshould be read with this correction therein that the same may conform tothe record of the case in the Patent Office.

Signed and sealed this 1st day of November, A. D. 1938.

Henry Van Arsdale (Seal) I Acting Commissioner of Patents.

CERTIFICATE OF CORRECTION. v a Patent No'. 2,1ll .,968. April 19, .1958.

WILLIAM c. NEIN, ET AL.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows Page 7,first ooimnn, line 59, claim}, strike out the wards "by the latter" andinsert the same after "way" in line 60, same claim; page 5,secondcolumn,- line 22, claim 11 before "timer" insert each; and line28, same claim, before "each" insert said; and that the said LettersPatent should be read with this correction therein that the same mayconform to the record of the case in the Patent Office.

Signed and sealed this 1st day of November, A. D. 1958.

Henry Van Ars'dale (Seal) Acting Commissioner of Patents.

